[Feature request] shortcut to open article in background tab

[mdkcore0]

Just an idea; I've used to use the b key to open an article in a background tab while on The Old Reader. it is very useful as I can scroll on other articles in my feed list and then later read the selected ones.

Also useful while reading comics, as some of them are big enough to not fit in the screen, or only shows a preview of the full comic.